• Journal of Forest and Environmental Science
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• 제32권3호
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• pp.311-322
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• 2016

Since forest trees form the basis of forest ecosystem, their prolong subsistence is crucial for various flora and fauna. The foremost challenges to sustain the forest ecosystem comprise of the declining forest tree population accompanied with structural changes due to afforestation and exploitation of forest area, environment changes, pests, pollution, and introgressive hybridization. For ex situ conservation approach, in vitro techniques encompass basic role for conserving tree genetic resources, predominantly where natural propagules like recalcitrant seed might not be appropriate for long-term conservation. The practice includes restricted growth techniques, conventional micropropagation, production and storage of synthetic seeds, and cryopreservation. Even though these practices have been applied chiefly to herbaceous species, but recently, woody species were also focused upon. Key conceptions, challenges and techniques for forest tree seed conservation are discussed briefly in this review with special emphasis on some successful cryopreservation approaches for long-term storage.

• 대한지하수환경학회지
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• 제7권3호
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• pp.133-140
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• 2000

초정지역은 세계 3대 광천수 생산지의 하나로서 지하수 이용업체들이 집중적으로 지하수 개발을 하고 있어 지하수자원의 고갈이 우려되고 있다. 본 연구에서는 초정지역의 지속적인 개발로 인해 장래 예측되는 지하수 장애에 대처하기 위해 수치모형을 이용하여 초정지역의 지하수 유통해석을 수행하였다. 해석 결과 동북쪽에 위치한 산간유역의 수위의 변화에 비하여, 하류 구릉지역에서는 양수정들을 중심으로 수위 강하가 급격하게 일어나고 있다. 이는 하류 구릉지역에 공장들이 밀집하여 있고 생활용수와 농업용수 또한 많은 양을 양수를 하는데 기인한다. 따라서 향후 지하수자원의 고갈이 우려되며, 이에 대한 대책이 심각하게 요구된다.

• ALGAE
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• 제28권4호
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• pp.355-363
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• 2013

The coralline alga, Corallina officinalis, is a widely distributed intertidal species in temperate coastal regions. It is usually exposed to high fluctuations of light intensity, light quality, temperature, and desiccation, all of which affect the temporal and spatial distribution as well as the morphology and the metabolism of this alga. In laboratory experiments we examined the effects of different light intensities (50, 100, and 200 ${\mu}mol$ photons $m^{-2}s^{-1}$) on photosynthesis, calcification, photosynthetic pigment contents (chlorophyll a and carotenoids), and growth rate of C. officinalis to clarify its photoacclimation strategies. Net photosynthesis, calcification and dissolution rates based on weight were not sensitive to irradiance. Although, photosynthesis and calcification did not clearly respond to light intensity, photosynthetic pigment contents were significantly lower at higher light intensities. In addition, higher irradiances induced significant enhancement of gross photosynthesis based on chlorophyll a. As a result, the specific growth rate was significantly stimulated by high light intensity. Our results suggest that photoacclimation of C. officinalis to different light conditions may be regulated to optimize growth.

• ALGAE
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• 제32권1호
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• pp.41-46
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• 2017

In rocky intertidal habitats, abiotic stress due to desiccation and thermal extremes increases with elevation because of tides. A study in Atlantic Canada showed that, at low elevations where conditions are benign due to the brief low tides, fucoid algal canopies (Ascophyllum nodosum and Fucus spp.) do not affect the structure of benthic communities. However, at middle and high elevations, where low tides last longer, fucoid canopies limit abiotic extremes and increase the richness (number of invertebrate and algal species, except fucoids) of benthic communities. Using the data from that study, this paper compares the intensity of facilitation and its importance (relative to all other sources of variation in richness) between middle and high elevations, which represent intermediate and high stress, respectively. Facilitation intensity was calculated as the percent increase in benthic richness between quadrats with low and high canopy cover, while the importance of facilitation was calculated as the percentage of variation in richness explained by canopy cover. Data for 689 quadrats spanning 350 km of coastline were used. Both the intensity and importance of facilitation were greater at middle elevations than at high elevations. As canopies do not affect benthic communities at low elevations, this study suggests that the facilitation-stress relationship at the community level is unimodal for this marine system. Such a pattern was found for some terrestrial systems dominated by canopy-forming plants. Thus, it might be ubiquitous in nature and, as further studies refine it, it might help to predict community-level facilitation depending on environmental stress.

• 한국작물학회지
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• 제25권4호
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• pp.10-16
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• 1980

벼의 내한성에 관여하는 생태 및 형태적인 특성을 찾기 위하여 수도과 능도 각 5품종씩을 가지고 파종상자에서 벼를 재배하고 건조처리한 후 다시 관수하여 위주상태에서 생육이 회복되는 정도를 비교하였으며 관련되는 식물체부위의 특성과의 관계를 구한 결과 다음과 같이 요약할 수 있였다. 1. 건조처리후 재생력은 수도가 육도보다 강하였고 수도에서는 인도형품종이 일본형 품종보다 강하였다. 2. 생육단암별 재생력은 생육초기에 가장 높았고 생육이 진전되면서 점점 낮아졌는데 어느 시기에서나 수도가 육종보다 높은 재생력을 나타내었다. 3. 초장과 엽면적의 차이는 건조처리후 재생력에 영향을 미치지 않았다. 4. 뿌리 발달의 특성에 주근의 두께와 뿌리의 총건물중은 수도보다 육도에서 높았으며 이것은 밭재배에서의 수량과 높은 정의 상관이 있었다.

• Journal of Ecology and Environment
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• 제35권1호
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• pp.51-58
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• 2012

In this study, we investigated carabid beetles residing in the wetlands to understand their ecological adaptation and strategy selection associated with restricted resources and habitat limitation. The species richness, abundance, seasonal activity, and spatial distribution of the carabid beetles between the Mujechi Wetlands (wetland sites) and Mt. Jeongjok (mountain sites) have been compared. A total of 1,733 individual beetles from 30 species were collected and classified at the studied sites. The wetland sites were identified as having lower species richness and abundance for carabid beetles when compared with the adjacent mountain sites, whereas these beetles were observed to be dominant in the wetland sites than in the adjacent mountain sites. Calosoma inquisitor cyanescens, Carabus sternbergi sternbergi, and Carabus jankowskii jankowskii species were dominant in both the wetland and mountain sites. These species showed significantly different seasonal activity patterns in the wetland sites relative to the mountain sites. Although the three listed carabid species were observed to be widely distributed throughout the wetland sites, they still showed preference for drier sites, which clearly shows a distinction in their habitats. The results of the spatial-temporal distribution of carabid beetles in the wetland sites reflect their special strategies regarding space and time partitioning for maintaining their population. The distribution patterns of carabid beetles in the wetland sites also showed the desiccation gradient and environmental changes prevalent in wetlands. Ecological surveys, which use carabid beetles in the wetlands, can then be performed when restoring wetlands and for establishing management practices for improving the habitat quality.

• 한국응용곤충학회지
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• 제39권3호
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• pp.199-205
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• 2000

곤충병원선충(Steinernema carpocapsae Weiser)의 지상부 해충에 대한 야외 방제 효과검증을 위해 화학 방제가 곤란한 파밤나방(Spodoptera exigua(Hubner))을 대상으로 엽면 살포시 시험을 실시하였다. 지상부 살포시 건조에 따른 선충의 생존력 감소를 막기 위해 바람직한 내건제들이(Alkyl glucoside, CMC, glycerol, Keltrol-F, Kunipia-G 및 Laponite LXG) 우선 비교 분석되었다. 이들 내건제 가운데 Keltrol-F(0.1%)가 선발되었다. 이 농도의 내건제가 포함된 선충을 밀도별로 파밤나방이 서식하는 포크에 엽면 살포 처리하여 1 ml당 5,000마리의 감염태 선충의 유효 방제 밀도를 결정하였다. 이 선충 밀도로 포장에 적용하였을 때 87.8%dml 파밤나방 방제 효과를 보였다.

• Journal of Microbiology and Biotechnology
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• 제27권4호
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• pp.747-758
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• 2017

Chronic wounds, pressure sores, lesions, and infections of microbial origin in bedridden, paralyzed, or malnutrition patients remain the object of study of many researchers. A variety of factors behind the development of these disorders are related to the patient's immune system, making it unable to respond effectively to the treatment of the wound. These factors can be properly controlled, giving particular importance to the ethiology and stage of the wound, as well as the time periods corresponding to the replacement of the dressings. The present research reports a novel foam/soft material, ${{\small}L}$-Cys-g-PCL, with an application for decubitus/pressure ulcers, especially for wounds with a difficult healing process due to infections and constant oxidation of the soft tissues. During this work, the interactions between S. aureus and ${{\small}L}$-Cys-g-PCL foam were studied under conditions that simulate decubitus ulcers; namely, pH and exudate. The effects of duration of grafting (1 or 8 h) and pH (7.0 and 8.9) on wettability, surface energy, swelling, and porosity were also evaluated. Results showed an effective microbicidal activity exhibiting an inhibition ratio of 99.73% against S. aureus. This new ${{\small}L}$-Cys-g-PCL soft material showed saftey to contact skin, ability to be shaped to fill in sunken holes (craters) - pressure ulcers stage III - and to act as a smart material responsive to pH, which can be tailored to develop better swelling properties at alkaline pH where exudates are normally higher, so as to address exudate self-cleaning and prevention of desiccation.

• 한국지구과학회지
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• 제31권1호
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• pp.8-17
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• 2010

기존 연구 결과와 최근의 야외 지질 조사를 통하여 소청도의 지질 개요와 스트로마톨라이트 화석 산지의 보존 상태를 간단히 소개한다. 분암 지역에서 보존 상태가 매우 양호한 새로운 스트로마톨라이트 화석 산지를 확인하였다. 또한 선착장 부근에서 평행 엽층과 습곡 구조가 발달한 지층의 노두를 발견하였는 바, 이는 소청도의 관문에 위치한 소청도의 중요 지질학적 상징 중의 하나로서 가치가 있는 것으로 생각된다. 소청도의 스트로마톨라이트 화석 산지는 다양하고 보존 상태가 양호하며 상원계의 묵천통과 멸악산통에 대비되는 후기 원생대의 스트로마톨라이트 화석 뿐만 아니라 물결 자국, 건열, 빗방울 자국 등의 다양한 퇴적 구조를 포함하고 있다. 소청도의 스트로마톨라이트 화석은 우리나라에서 가장 오래된 화석 천연기념물로서 정밀한 학술 조사가 이루어져야 하며, 국가적인 보존 관리 되어야 한다.

• Journal of Applied Biological Chemistry
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• 제51권6호
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• pp.307-314
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• 2008

To explore the optimal conditions for the removal of $H_{2}S$ gas by biofiltration, various conditions, including inlet $H_{2}S$ concentration, flow rate, moisture, and cell number, were examined. Heterotrophic bacteria were isolated from the compost of the animal excreta. A strain that effectively removed $H_{2}S$ was selected and identified as Rhodococcus rhodochrous B261 by analysis of its 16S rDNA sequence. A cell number of $10^{7}\;cfu/g^{-}compost$ was sufficient to dominate the microbiota, and an effective removal was observed at $H_{2}S$ gas concentrations below 220 mg/L. The moisture content of 33-38% was suitable for activation of the microbial activity and delaying the desiccation. Higher flow rates resulted in lower removal rates of the $H_{2}S$ gas. Under the conditions of $10^7\;cfu/g^{-}compost$, $H_{2}S$ gas concentrations of 220 mg/L, and moisture content of 33-38%, the inlet $H_{2}S$ gas concentrations of 120 and 400 mg/L were completely removed for 34 and 12 days, respectively. The amount of sulfur removed was $2.99{\times}10^{-9}H_{2}S-S/cell$, which was suggested as the amount of sulfur removed by a single cell. The biofilter consisting of the compost and R. rhodochrous B261 could be suitable for a long-term biofilteration for the removal of $H_{2}S$ and other malodorous compounds.